I went with the Kingmax PC2700 5ns 256 RAM at first. It ran great at 340Mhz, CAS2, 2.5V. No BSOD's, Prime95 ran forever. I decided to test it with Memtest 86. Uh-oh. I got errors in some of the tests. Tried lowering the speed (to as low as 250Mhz!) and upping the CAS but still got errors. Called Kingmax tech support and he said I had bad RAM. Exchanged it for 2 more sticks, ran Memtest again. This time I got over 5000 errors!
So I got myself a 512Mb stick of the brand-new Corsair PC2700 XMS RAM. Ran Memtest 86 on it at 340Mhz, CAS2, 2.5V. Ran perfect for 10 hrs with NO errors. I think I'll stick with the Corsair RAM.
I don't know if the Kingmax is no good or maybe there's some issues with it and my MoBo (an Asus P4B266 Intel 845 chipset). Did I get 4 bad sticks of Kingmax?? I doubt it. Sent an email to Asus tech support to see if there's any problems with Asus/Kingmax but haven't heard back. Meanwhile the Corsair is working flawlessly.